Description 1.Accuracy:1±2 words 2. Range: AC voltage: AC 40.0-300.0V or AC 250.0-450.0V (You should select one type of the meter in your order) The measuring range 40-300V without limitation, and it can be used in grid power, photovoltaic and inverter current 250-450V only can use for 380V AC Current: AC 0-100.0A , the current resolution is 0.01A . Frequence: 45.0Hz 65.0Hz Power Factor: 0.00-1.00PF Electric Power: 0-450000W, the electric power resolution is 0.1W when measure electric power between 0-9999.9W, otherwise the electric power resolution is 1W. Electric Energy: 0-99999kwh, the display of electric energy resolution is 0.01kwh when measure electric engery between 0-999.99kwh, the display of electric energy resolution is 0.1kwh when measure electric engery between 1000.0-9999.9kwh and the display of electric energy resolution is 1kwh when measure electric engery larger than 9999.9kwh 3. Speed: 2 times per second 4. size: 54 × 80 × 64mm 5. Installation: Din-Rail Application Method 1. Connect the measure voltage to the 1 and 2 terminal 2. Connections of meter with internal current transformer . Make the wire through the hole in the meter and the direction chose arbitrarily. 3. Connections of meter with external current transformer . Make the wire through the hole in the meter, and connect the two wires of the secondary transformer to the 3 and 4 terminal. 4. When power on, the meter display the measure parameters. 5. When power on, you can press the button of SAM CK last for 5 seconds, then the electric energy will to be zero and start to cumulate when release the button. And when power off, the meter can save the value of electric energy and go on cumulating data when the meter power-on next. Attention: The meter can only use for measure 45-65Hz AC city electricity. Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you! Please allow 1-2cm measuring deviation due to manual measurement.